Powered roll-in cots

ABSTRACT

According to one embodiment, a roll-in cot may include a support frame, a pair of back legs, a pair of front legs, and a cot actuation system. The pair of back legs and the pair of front legs can be slidingly coupled to the support frame. Each of the pair of front legs can include a front wheel and an intermediate load wheel. The intermediate load wheel is offset from the front wheel by a load wheel distance. A front actuator can raise the pair of front legs such that the front wheel and the intermediate load wheel of each of the pair of front legs are aligned along a loading level. The intermediate load wheel of each of the pair of front legs can be offset from the pair of back legs by a loading span. The load wheel distance can be greater than the loading span.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 15/335,865, filed Oct. 27, 2016, which is a divisional applicationof U.S. application Ser. No. 14/245,107, filed Apr. 4, 2014, now U.S.Pat. No. 9,510,982, which is a continuation-in-part of U.S. applicationSer. No. 13/520,627, filed Dec. 21, 2012, now U.S. Pat. No. 9,233,033,which is a U.S. National Stage of International Application No.PCT/US2011/021069, filed Jan. 13, 2011, which claims the benefit of U.S.Provisional Application No. 61/294,658, filed Jan. 13, 2010.

TECHNICAL FIELD

The present disclosure is generally related to emergency cots, and isspecifically directed to powered roll-in cots.

BACKGROUND

There is a variety of emergency cots in use today. Such emergency cotsmay be designed to transport and load bariatric patients into anambulance.

For example, the PROFlexX® cot, by Ferno-Washington, Inc. of Wilmington,Ohio U.S.A., is a manually actuated cot that may provide stability andsupport for loads of about 700 pounds (about 317.5 kg). The PROFlexX®cot includes a patient support portion that is attached to a wheeledundercarriage. The wheeled under carriage includes an X-frame geometrythat can be transitioned between nine selectable positions. Onerecognized advantage of such a cot design is that the X-frame providesminimal flex and a low center of gravity at all of the selectablepositions. Another recognized advantage of such a cot design is that theselectable positions may provide better leverage for manually liftingand loading bariatric patients.

Another example of a cot designed for bariatric patients, is thePOWERFlexx® Powered Cot, by Ferno-Washington, Inc. The POWERFlexx®Powered Cot includes a battery powered actuator that may providesufficient power to lift loads of about 700 pounds (about 317.5 kg). Onerecognized advantage of such a cot design is that the cot may lift abariatric patient up from a low position to a higher position, i.e., anoperator may have reduced situations that require lifting the patient.

A further variety is a multipurpose roll-in emergency cot having apatient support stretcher that is removably attached to a wheeledundercarriage or transporter. The patient support stretcher when removedfor separate use from the transporter may be shuttled aroundhorizontally upon an included set of wheels. One recognized advantage ofsuch a cot design is that the stretcher may be separately rolled into anemergency vehicle such as station wagons, vans, modular ambulances,aircrafts, or helicopters, where space and reducing weight is a premium.

Another advantage of such a cot design is that the separated stretchermay be more easily carried over uneven terrain and out of locationswhere it is impractical to use a complete cot to transfer a patient.Example of such prior art cots can be found in U.S. Pat. Nos. 4,037,871,4,921,295, and International Publication No. WO01701611.

Although the foregoing multipurpose roll-in emergency cots have beengenerally adequate for their intended purposes, they have not beensatisfactory in all aspects. For example, the foregoing emergency cotsare loaded into ambulances according to loading processes that requireat least one operator to support the load of the cot for a portion ofthe respective loading process.

SUMMARY

The embodiments described herein address are directed to a versatilemultipurpose roll-in emergency cot which may provide improved managementof the cot weight, improved balance, and/or easier loading at any cotheight, while being rollable into various types of rescue vehicles, suchas ambulances, vans, station wagons, aircrafts and helicopters.

According to one embodiment, In one embodiment, a roll-in cot caninclude a support frame, a back carriage member, a pair of back legs, apair of front legs and a cot actuation system. The support frame caninclude a front end and a back end. The back carriage member can beslidingly engaged with the support frame. The pair of back legs can berotatably coupled to the back carriage member. Each of the pair of backlegs can include a wheel linkage and a back wheel coupled to the wheellinkage. Each of the pair of back legs can define a back leg span thatextends from the back carriage member through the wheel linkage. Thepair of front legs can be slidingly coupled to the support frame. Eachof the pair of front legs can include a front wheel and an intermediateload wheel having an axis of rotation. The intermediate span can bedemarcated by the axis of rotation of the intermediate load wheel andthe back carriage member. The cot actuation system can include a frontactuator that moves the pair of front legs and a back actuator thatmoves the pair of back legs. The front actuator can retract the pair offront legs such that the intermediate load wheel is supported by aloading surface. The back actuator can retract the pair of back legssuch that the back wheel is supported by a lower surface. The lowersurface can be lower than the loading surface. A back leg angle θ can beformed between the back leg span and the intermediate span. The back legangle θ can be an acute angle.

According to another embodiment, a roll-in cot may include a supportframe, a pair of back legs, a pair of front legs, and a cot actuationsystem. The support frame may include a front end, and a back end. Thepair of back legs can be slidingly coupled to the support frame. Thepair of front legs can be slidingly coupled to the support frame. Eachof the pair of front legs can include a front wheel and an intermediateload wheel. The intermediate load wheel is offset from the front wheelby a load wheel distance. The cot actuation system can include a frontactuator that moves the pair of front legs and a back actuator thatmoves the pair of back legs. The front actuator can raise the pair offront legs such that the front wheel and the intermediate load wheel ofeach of the pair of front legs are aligned along a loading level. Theintermediate load wheel of each of the pair of front legs can be offset,along the loading level, from the pair of back legs by a loading span.The load wheel distance can be greater than the loading span.

According to yet another embodiment, a roll-in cot can include a supportframe, a pair of legs slidingly and pivotally engaged with the supportframe, and an actuator coupled to the pair of legs. The actuator can beoperable to actuate the pair of legs such that the pair of legs slideand rotate with respect to the support frame. A method for actuating theroll-in cot can include receiving from an actuator sensor, automaticallywith a processor, a load signal indicative of a force acting upon orexerted by the actuator. A control signal indicative of a command tochange a height of the roll-in cot can be received. The actuator can becaused to actuate the pair of legs relatively slowly. The actuator canbe determined, automatically with the processor, to be unloaded basedupon the load signal. The actuator can be caused, automatically with theprocessor, to actuate the pair of legs at a higher rate. The pair oflegs can be actuated at the higher rate after the actuator is determinedto be unloaded.

According to a further embodiment, a roll-in cot can include a supportframe, a pair of front legs, a pair of back legs, a pair of back hingemembers, and a cot actuation system. The support frame can include afront end, and a back end. The pair of front legs can be slidinglycoupled to the support frame. The pair of back legs can be slidinglycoupled to the support frame. Each of the pair of back legs can includea sinuous internal edge that faces the front end of the support frame.The sinuous internal edge can form an upper angle β. The upper angle βcan be an obtuse angle. Each of the pair of back hinge members can bepivotingly coupled to the support frame at a first end and pivotinglycoupled to one of the pair of back legs at a second end. The upper angleβ of the sinuous internal edge can be located above the second end ofone of the pair of back hinge members. The cot actuation system caninclude a front actuator that moves the pair of front legs and a backactuator that moves the pair of back legs.

According to a further embodiment, a roll-in cot can include a supportframe, a pair of front legs, a pair of back legs, and a cot actuationsystem. The support frame can include a front end, and a back end. Thefront end can include a pair of front load wheels. The pair of back legscan be slidingly coupled to the support frame. The pair of front legscan be slidingly coupled to the support frame. Each of the front legscan include a front wheel and an intermediate load wheel. The cotactuation system can include a front actuator that moves the pair offront legs and a back actuator that moves the pair of back legs. Whenthe pair of front legs is retracted towards the support frame, theroll-in cot can be configured to be load balanced forward of theintermediate load wheel.

These and additional features provided by the embodiments of the presentdisclosure will be more fully understood in view of the followingdetailed description, in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed description of specific embodiments of thepresent disclosures can be best understood when read in conjunction withthe following drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1 is a perspective view depicting a cot according to one or moreembodiments described herein;

FIG. 2 is a top view depicting a cot according to one or moreembodiments described herein;

FIG. 3 is a perspective view depicting a cot according to one or moreembodiments described herein;

FIG. 4 is a perspective view depicting a cot according to one or moreembodiments described herein;

FIGS. 5A-5C is a side view depicting a raising and/or lower sequence ofa cot according to one or more embodiments described herein;

FIGS. 6A-6E is a side view depicting a loading and/or unloading sequenceof a cot according to one or more embodiments described herein;

FIG. 7A is a perspective view depicting an actuator according to one ormore embodiments described herein;

FIG. 7B schematically depicts an actuator according to one or moreembodiments described herein;

FIG. 8 perspective view depicting a cot according to one or moreembodiments described herein;

FIG. 9 schematically depicts a timing belt and gear system according toone or more embodiments described herein;

FIG. 10 is a perspective view depicting a hook engagement bar accordingto one or more embodiments described herein;

FIG. 11 schematically depicts a tension member and pulley systemaccording to one or more embodiments described herein; and

FIG. 12 schematically depicts the back legs of FIG. 6A in isolationaccording to one or more embodiments described herein.

The embodiments set forth in the drawings are illustrative in nature andnot intended to be limiting of the embodiments described herein.Moreover, individual features of the drawings and embodiments will bemore fully apparent and understood in view of the detailed description.

DETAILED DESCRIPTION

Referring to FIG. 1, a roll-in cot 10 for transport and loading isshown. The roll-in cot 10 comprises a support frame 12 comprising afront end 17, and a back end 19. As used herein, the front end 17 issynonymous with the loading end, i.e., the end of the roll-in cot 10which is loaded first onto a loading surface. Conversely, as usedherein, the back end 19 is the end of the roll-in cot 10 which is loadedlast onto a loading surface. Additionally it is noted, that when theroll-in cot 10 is loaded with a patient, the head of the patient may beoriented nearest to the front end 17 and the feet of the patient may beoriented nearest to the back end 19. Thus, the phrase “head end” may beused interchangeably with the phrase “front end,” and the phrase “footend” may be used interchangeably with the phrase “back end.”Furthermore, it is noted that the phrases “front end” and “back end” areinterchangeable. Thus, while the phrases are used consistentlythroughout for clarity, the embodiments described herein may be reversedwithout departing from the scope of the present disclosure. Generally,as used herein, the term “patient” refers to any living thing orformerly living thing such as, for example, a human, an animal, a corpseand the like.

Referring collectively to FIGS. 2 and 3, the front end 17 and/or theback end 19 may be telescoping. In one embodiment, the front end 17 maybe extended and/or retracted (generally indicated in FIG. 2 by arrow217). In another embodiment, the back end 19 may be extended and/orretracted (generally indicated in FIG. 2 by arrow 219). Thus, the totallength between the front end 17 and the back end 19 may be increasedand/or decreased to accommodate various sized patients. Furthermore, asdepicted in FIG. 3, the front end 17 may comprise telescoping lifthandles 150. The telescoping lift handles 150 may telescope away fromthe support frame 12 to provide lifting leverage and telescope towardsthe support frame 12 to be stored. In some embodiments, the telescopinglift handles 150 are pivotingly coupled to the support frame 12 and arerotatable from a vertical handle orientation to a side handleorientation, and vice versa. The telescoping lift handles 150 may lockin the vertical handle orientation and the side handle orientation. Inone embodiment, when the telescoping lift handles 150 are in the sidehandle orientation, the telescoping lifting handles 150 provide agripping surface adjacent to the support frame 12 and are eachconfigured to be gripped by a hand with the palm substantially facing upand/or down. Conversely, when the telescoping lift handles 150 are inthe vertical handle orientation, the telescoping lifting handles 150 mayeach be configured to be gripped by a hand with the thumb substantiallypointing up and/or down.

Referring collectively to FIGS. 1 and 2, the support frame 12 maycomprise a pair of parallel lateral side members 15 extending betweenthe front end 17 and the back end 19. Various structures for the lateralside members 15 are contemplated. In one embodiment, the lateral sidemembers 15 may be a pair of spaced metal tracks. In another embodiment,the lateral side members 15 comprise an undercut portion 115 that isengageable with an accessory clamp (not depicted). Such accessory clampsmay be utilized to removably couple patient care accessories such as apole for an IV drip to the undercut portion 115. The undercut portion115 may be provided along the entire length of the lateral side membersto allow accessories to be removably clamped to many different locationson the roll-in cot 10.

Referring again to FIG. 1, the roll-in cot 10 also comprises a pair ofretractable and extendible front legs 20 coupled to the support frame12, and a pair of retractable and extendible back legs 40 coupled to thesupport frame 12. The roll-in cot 10 may comprise any rigid materialsuch as, for example, metal structures or composite structures.Specifically, the support frame 12, the front legs 20, the back legs 40,or combinations thereof may comprise a carbon fiber and resin structure.As is described in greater detail herein, the roll-in cot 10 may beraised to multiple heights by extending the front legs 20 and/or theback legs 40, or the roll-in cot 10 may be lowered to multiple heightsby retracting the front legs 20 and/or the back legs 40. It is notedthat terms such as “raise,” “lower,” “above,” “below,” and “height” areused herein to indicate the distance relationship between objectsmeasured along a line parallel to gravity using a reference (e.g. asurface supporting the cot).

In specific embodiments, the front legs 20 and the back legs 40 may eachbe coupled to the lateral side members 15. Referring to FIG. 8, thefront legs 20 may comprise front carriage members 28 slidingly coupledto the tracks of lateral side members 15, and the back legs 40 may alsocomprise back carriage members 48 slidingly coupled to the tracks oflateral side members 15. Referring to FIGS. 5A-6E and 10, when theroll-in cot 10 is raised or lowered, the carriage members 28 and/or 48slide inwardly or outwardly, respectively along the tracks of thelateral side members 15.

As shown in FIGS. 5A-6E, the front legs 20 and the back legs 40 maycross each other, when viewing the cot from a side, specifically atrespective locations where the front legs 20 and the back legs 40 arecoupled to the support frame 12 (e.g., the lateral side members 15(FIGS. 1-4)). As shown in the embodiment of FIG. 1, the back legs 40 maybe disposed inwardly of the front legs 20, i.e., the front legs 20 maybe spaced further apart from one another than the back legs 40 arespaced from one another such that the back legs 40 are each locatedbetween the front legs 20. Additionally, the front legs 20 and the backlegs 40 may comprise front wheels 26 and back wheels 46 which enable theroll-in cot 10 to roll.

In one embodiment, the front wheels 26 and back wheels 46 may be swivelcaster wheels or swivel locked wheels. As is described below, as theroll-in cot 10 is raised and/or lowered, the front wheels 26 and backwheels 46 may be synchronized to ensure that the plane of the roll-incot 10 and the plane of the wheels 26, 46 are substantially parallel.For example, the back wheels 46 may each be coupled to a back wheellinkage 47 and the front wheels 26 may each be coupled to a front wheellinkage 27. As the roll-in cot 10 is raised and/or lowered, the frontwheel linkages 27 and the back wheel linkages 47 may be rotated tocontrol the plane of the wheels 26, 46.

A locking mechanism (not depicted) may be disposed in one of the frontwheel linkages 27 and the back wheel linkages 47 to allow an operator toselectively enable and/or disable wheel direction locking. In oneembodiment, a locking mechanism is coupled to one of the front wheels 26and/or one of the back wheels 46. The locking mechanism transitions thewheels 26, 46 between a swiveling state and a directionally lockedstate. For example, in a swiveling state the wheels 26, 46 may beallowed to swivel freely which enables the roll-in cot 10 to be easilyrotated. In the directionally locked state, the wheels 26, 46 may beactuated by an actuator (e.g., a solenoid actuator, a remotely operatedservomechanism and the like) into a straight orientation, i.e., thefront wheels 26 are oriented and locked in a straight direction and theback wheels 46 swivel freely such that an operator pushing from the backend 19 would direct the roll-in cot 10 forward.

Referring again to FIG. 1, the roll-in cot 10 may also comprise a cotactuation system comprising a front actuator 16 configured to move thefront legs 20 and a back actuator 18 configured to move the back legs40. The cot actuation system may comprise one unit (e.g., a centralizedmotor and pump) configured to control both the front actuator 16 and theback actuator 18. For example, the cot actuation system may comprise onehousing with one motor capable to drive the front actuator 16, the backactuator 18, or both utilizing valves, control logic and the like.Alternatively as depicted in FIG. 1, the cot actuation system maycomprise separate units configured to control the front actuator 16 andthe back actuator 18 individually. In this embodiment, the frontactuator 16 and the back actuator 18 may each include separate housingswith individual motors to drive the actuators 16 or 18. While theactuators are shown as hydraulic actuators or chain lift actuators inthe present embodiments, various other structures are contemplated asbeing suitable.

Referring to FIG. 1, the front actuator 16 is coupled to the supportframe 12 and configured to actuate the front legs 20 and raise and/orlower the front end 17 of the roll-in cot 10. Additionally, the backactuator 18 is coupled to the support frame 12 and configured to actuatethe back legs 40 and raise and/or lower the back end 19 of the roll-incot 10. The cot actuation system may be motorized, hydraulic, orcombinations thereof. Furthermore, it is contemplated that the roll-incot 10 may be powered by any suitable power source. For example, theroll-in cot 10 may comprise a battery capable of supplying a voltage of,such as, about 24 V nominal or about 32 V nominal for its power source.

The front actuator 16 and the back actuator 18 are operable to actuatethe front legs 20 and back legs 40, simultaneously or independently. Asshown in FIGS. 5A-6E, simultaneous and/or independent actuation allowsthe roll-in cot 10 to be set to various heights and angles with respectto a surface supporting the roll-in cot 10.

Any actuator suitable to raise and lower the support frame 12 as well asretract the front legs 20 and back legs 40 is contemplated herein. Asdepicted in FIGS. 3 and 8, the front actuator 16 and/or the backactuator 18 may include chain lift actuators (e.g., chain lift actuatorsby Serapid, Inc. of Sterling Heights, Mich. U.S.A.). Alternatively, thefront actuator 16 and/or the back actuator 18 may also include wheel andaxle actuators, hydraulic jack actuators, hydraulic column actuators,telescopic hydraulic actuators electrical motors, pneumatic actuators,hydraulic actuators, linear actuators, screw actuators, and the like.For example, the actuators described herein may be capable of providinga dynamic force of about 350 pounds (about 158.8 kg) and a static forceof about 500 pounds (about 226.8 kg). Furthermore, the front actuator 16and the back actuator 18 may be operated by a centralized motor systemor multiple independent motor systems.

In one embodiment, schematically depicted in FIGS. 1-2 and 7A-7B, thefront actuator 16 and the back actuator 18 comprise hydraulic actuatorsfor actuating the roll-in cot 10. In the embodiment depicted in FIG. 7A,the front actuator 16 and the back actuator 18 are dual piggy backhydraulic actuators. The dual piggy back hydraulic actuator comprisesfour hydraulic cylinders with four extending rods that are piggy backed(i.e., mechanically coupled) to one another in pairs. Thus, the dualpiggy back actuator comprises a first hydraulic cylinder with a firstrod, a second hydraulic cylinder with a second rod, a third hydrauliccylinder with a third rod and a fourth hydraulic cylinder with a fourthrod.

In the depicted embodiment, the dual piggy back hydraulic actuatorcomprises a rigid support frame 180 that is substantially “H” shaped(i.e., two vertical portions connected by a cross portion). The rigidsupport frame 180 comprises a cross member 182 that is coupled to twovertical members 184 at about the middle of each of the two verticalmembers 184. A pump motor 160 and a fluid reservoir 162 are coupled tothe cross member 182 and in fluid communication. In one embodiment, thepump motor 160 and the fluid reservoir 162 are disposed on oppositesides of the cross member 182 (e.g., the fluid reservoir 162 disposedabove the pump motor 160). Specifically, the pump motor 160 may be abrushed bi-rotational electric motor with a peak output of about 1400watts. The rigid support frame 180 may include additional cross membersor a backing plate to provide further rigidity and resist motion of thevertical members 184 with respect to the cross member 182 duringactuation.

Each vertical member 184 comprises a pair of piggy backed hydrauliccylinders (i.e., a first hydraulic cylinder and a second hydrauliccylinder or a third hydraulic cylinder and a fourth hydraulic cylinder)wherein the first cylinder extends a rod in a first direction and thesecond cylinder extends a rod in a substantially opposite direction.When the cylinders are arranged in one master-slave configuration, oneof the vertical members 184 comprises an upper master cylinder 168 and alower master cylinder 268. The other of the vertical members 184comprises an upper slave cylinder 169 and a lower slave cylinder 269. Itis noted that, while master cylinders 168, 268 are piggy backed togetherand extend rods 165, 265 in substantially opposite directions, mastercylinders 168, 268 may be located in alternate vertical members 184and/or extend rods 165, 265 in substantially the same direction.

Referring now to FIG. 7B, a master-slave hydraulic circuit is formed byplacing two cylinders in fluidic communication. Specifically, the uppermaster cylinder 168 is in fluidic communication with the upper slavecylinder 169 and may communicate hydraulic fluid via the fluidconnection 170. The pump motor 160 pressurizes hydraulic fluid stored inthe fluid reservoir 162. The upper master cylinder 168 receivespressurized hydraulic fluid from the pump motor 160 in a first mastervolume 172 disposed on one side of the upper master piston 164. Aspressurized hydraulic fluid displaces the upper master piston 164, theupper master rod 165, which is coupled to the upper master piston 164,extends out of the upper master cylinder 168 and a secondary hydraulicfluid is displaced from a second master volume 174 disposed on anotherside of the upper master piston 164. The secondary hydraulic fluid iscommunicated through the fluid connection 170 and received in a slavevolume 176 disposed on one side of upper slave piston 166. Since thevolume of secondary hydraulic fluid displaced from the upper mastercylinder 168 is substantially equal to the slave volume 176, the upperslave piston 166 and the upper master piston 164 are displaced atsubstantially the same speed and travel substantially the same distance.Thus, the upper slave rod 167, which is coupled to the upper slavepiston 166, and the upper master rod 165 are displaced at substantiallythe same speed and travel substantially the same distance.

Referring back to FIG. 7A, a similar master-slave hydraulic circuit isformed by placing the lower master cylinder 268 in fluidic communicationwith the lower slave cylinder 269. Thus, the lower master rod 265 andthe lower slave rod 267 are displaced at substantially the same speedand travel substantially the same distance. In another embodiment, aflow divider may be used to regulate the distribution of pressurizedhydraulic fluid from pump motor 160 and substantially equally divide theflow between the upper master cylinder 168 and the lower master cylinder268 to cause all of the rods 165, 167, 265, 267 to move in unison, i.e.,the fluid can be divided equally to both master cylinders which causesthe upper and lower rods to move at the same time. The direction of thedisplacement of the rods 165, 167, 265, 267 is controlled by pump motor160, i.e., the pressure of the hydraulic fluid may be set relativelyhigh to supply fluid to the master cylinders for raising thecorresponding legs and set relatively low to pull hydraulic fluid fromthe master cylinders for lowering the corresponding legs.

While the cot actuation system is typically powered, the cot actuationsystem may also comprise a manual release component (e.g., a button,tension member, switch, linkage or lever) configured to allow anoperator to raise or lower the front and back actuators 16, 18 manually.In one embodiment, the manual release component disconnects the driveunits of the front and back actuators 16, 18 to facilitate manualoperation. Thus, for example, the wheels 26, 46 may remain in contactwith the ground when the drive units are disconnected and the roll-incot 10 is manually raised. The manual release component may be disposedat various positions on the roll-in cot 10, for example, on the back end19 or on the side of the roll-in cot 10.

To determine whether the roll-in cot 10 is level, sensors (not depicted)may be utilized to measure distance and/or angle. For example, the frontactuator 16 and the back actuator 18 may each comprise encoders whichdetermine the length of each actuator. In one embodiment, the encodersare real time encoders which are operable to detect movement of thetotal length of the actuator or the change in length of the actuatorwhen the cot is powered or unpowered (i.e., manual control). Whilevarious encoders are contemplated, the encoder, in one commercialembodiment, may be the optical encoders produced by Midwest MotionProducts, Inc. of Watertown, Minn. U.S.A. In other embodiments, the cotcomprises angular sensors that measure actual angle or change in anglesuch as, for example, potentiometer rotary sensors, hall effect rotarysensors and the like. The angular sensors can be operable to detect theangles of any of the pivotingly coupled portions of the front legs 20and/or the back legs 40. In one embodiment, angular sensors are operablycoupled to the front legs 20 and the back legs 40 to detect thedifference between the angle of the front leg 20 and the angle of theback leg 40 (angle delta). A loading state angle may be set to an anglesuch as about 20° or any other angle that generally indicates that theroll-in cot 10 is in a loading state (indicative of loading and/orunloading). Thus, when the angle delta exceeds the loading state anglethe roll-in cot 10 may detect that it is in a loading state and performcertain actions dependent upon being in the loading state.

It is noted that the term “sensor,” as used herein, means a device thatmeasures a physical quantity and converts it into a signal which iscorrelated to the measured value of the physical quantity. Furthermore,the term “signal” means an electrical, magnetic or optical waveform,such as current, voltage, flux, DC, AC, sinusoidal-wave,triangular-wave, square-wave, and the like, capable of being transmittedfrom one location to another.

Referring now to FIG. 3, the front legs 20 may further comprise a frontcross beam 22 extending horizontally between and moveable with the pairof front legs 20. The front legs 20 also comprise a pair of front hingemembers 24 pivotingly coupled to the support frame 12 at one end andpivotingly coupled to the front legs 20 at the opposite end. Similarly,the pair of back legs 40 comprise a back cross beam 42 extendinghorizontally between and moveable with the pair of back legs 40. Theback legs 40 also comprise a pair of back hinge members 44 pivotinglycoupled to the support frame at one end and pivotingly coupled to one ofthe back legs 40 at the opposite end. In specific embodiments, the fronthinge members 24 and the back hinge members 44 may be pivotingly coupledto the lateral side members 15 of the support frame 12. As used herein,“pivotingly coupled” means that two objects coupled together to resistlinear motion and to facilitate rotation or oscillation between theobjects. For example, front and back hinge members 24, 44 do not slidewith the front and back carriage members 28, 48, respectively, but theyrotate or pivot as the front and back legs 20, 40 are raised, lowered,retracted, or released. As shown in the embodiment of FIG. 3, the frontactuator 16 may be coupled to the front cross beam 22, and the backactuator 18 may be coupled to the back cross beam 42.

Referring to FIG. 4, the front end 17 may also comprise a pair of frontload wheels 70 configured to assist in loading the roll-in cot 10 onto aloading surface 500 (e.g., the floor of an ambulance). The roll-in cot10 may comprise sensors operable to detect the location of the frontload wheels 70 with respect to a loading surface 500 (e.g., distanceabove the surface or contact with the surface). In one or moreembodiments, the front load wheel sensors comprise touch sensors,proximity sensors, or other suitable sensors effective to detect whenthe front load wheels 70 are above a loading surface 500. In oneembodiment, the front load wheel sensors are ultrasonic sensors alignedto detect directly or indirectly the distance from the front load wheels70 to a surface beneath the load wheels. Specifically, the ultrasonicsensors, described herein, may be operable to provide an indication whena surface is within a definable range of distance from the ultrasonicsensor (e.g., when a surface is greater than a first distance but lessthan a second distance). Thus, the definable range may be set such thata positive indication is provided by the sensor when a portion of theroll-in cot 10 is in proximity to a loading surface 500.

In a further embodiment, multiple front load wheel sensors may be inseries, such that the front load wheel sensors are activated only whenboth front load wheels 70 are within a definable range of the loadingsurface 500 (i.e., distance may be set to indicate that the front loadwheels 70 are in contact with a surface). As used in this context,“activated” means that the front load wheel sensors send a signal to thecontrol box 50 that the front load wheels 70 are both above the loadingsurface 500. Ensuring that both front load wheels 70 are on the loadingsurface 500 may be important, especially in circumstances when theroll-in cot 10 is loaded into an ambulance at an incline.

In the embodiments described herein, the control box 50 comprises or isoperably coupled to a processor and a memory. The processor may be anintegrated circuit, a microchip, a computer, or any other computingdevice capable of executing machine readable instructions. Theelectronic memory may be RAM, ROM, a flash memory, a hard drive, or anydevice capable of storing machine readable instructions. Additionally,it is noted that distance sensors may be coupled to any portion of theroll-in cot 10 such that the distance between a lower surface andcomponents such as, for example, the front end 17, the back end 19, thefront load wheels 70, the front wheels 26, the intermediate load wheels30, the back wheels 46, the front actuator 16 or the back actuator 18may be determined.

In further embodiments, the roll-in cot 10 has the capability tocommunicate with other devices (e.g., an ambulance, a diagnostic system,a cot accessory, or other medical equipment). For example, the controlbox 50 may comprise or may be operably coupled to a communication memberoperable to transmit and receive a communication signal. Thecommunication signal may be a signal that complies with Controller AreaNetwork (CAN) protocol, Bluetooth protocol, ZigBee protocol, or anyother communication protocol.

The front end 17 may also comprise a hook engagement bar 80, which istypically disposed between the front load wheels 70, and is operable toswivel forward and backward. While the hook engagement bar 80 of FIG. 3is U-shaped, various other structures such as hooks, straight bars, arcshaped bars, etc. may also be used. As shown in FIG. 4, the hookengagement bar 80 is operable to engage with a loading surface hook 550on a loading surface 500. Loading surface hooks 550 are commonplace onthe floors of ambulances. The engagement of the hook engagement bar 80and the loading surface hook 550 may prevent the roll-in cot 10 fromsliding backwards from the loading surface 500. Moreover, the hookengagement bar 80 may comprise a sensor (not shown) which detects theengagement of the hook engagement bar 80 and the loading surface hook550. The sensor may be a touch sensor, a proximity sensor, or any othersuitable sensor operable to detect the engagement of the loading surfacehook 550. In one embodiment, the engagement of the hook engagement bar80 and the loading surface hook 550 may be configured to activate thefront actuator 16 and thereby allow for retraction of the front legs 20for loading onto the loading surface 500.

Referring still to FIG. 4, the front legs 20 may comprise intermediateload wheels 30 attached to the front legs 20. In one embodiment, theintermediate load wheels 30 may be disposed on the front legs 20adjacent the front cross beam 22. Like the front load wheels 70, theintermediate load wheels 30 may comprise a sensor (not shown) which areoperable to measure the distance the intermediate load wheels 30 arefrom a loading surface 500. The sensor may be a touch sensor, aproximity sensor, or any other suitable sensor operable to detect whenthe intermediate load wheels 30 are above a loading surface 500. As isexplained in greater detail herein, the load wheel sensor may detectthat the wheels are over the floor of the vehicle, thereby allowing theback legs 40 to safely retract. In some additional embodiments, theintermediate load wheel sensors may be in series, like the front loadwheel sensors, such that both intermediate load wheels 30 must be abovethe loading surface 500 before the sensors indicate that the load wheelsare above the loading surface 500 i.e., send a signal to the control box50. In one embodiment, when the intermediate load wheels 30 are within aset distance of the loading surface the intermediate load wheel sensormay provide a signal which causes the control box 50 to activate theback actuator 18. Although the figures depict the intermediate loadwheels 30 only on the front legs 20, it is further contemplated thatintermediate load wheels 30 may also be disposed on the back legs 40 orany other position on the roll-in cot 10 such that the intermediate loadwheels 30 cooperate with the front load wheels 70 to facilitate loadingand/or unloading (e.g., the support frame 12).

Additionally as shown in FIGS. 8 and 11, the roll-in cot 10 can comprisea tension member and pulley system 200 comprising carriage tensionmembers 120 coupled to the front carriage members 28 and the backcarriage members 48. A carriage tension member 120 forms a loop thatlinks each of the front carriage members 28 to one another. The carriagetension member 120 is slidingly engaged with pulleys 122 and extendsthrough the front carriage members 28. Similarly, a carriage tensionmember 120 forms a loop that links each of the back carriage members 48to one another. The carriage tension member 120 is slidingly engagedwith pulleys 122 and extends through the back carriage members 48. Thecarriage tension members 120 ensure the front carriage members 28 andthe back carriage members 48 move (generally denoted by arrows in FIG.11) in unison, i.e., the front legs 20 move in unison and the back legs40 move in unison.

By coupling carriage tension members 120 both of the front carriagemembers 28 and both of the back carriage members 48, the pulley systemensures parallel movement of the front legs 20 or back legs 40, reducesside to side rocking of the support frame 12, and reduces bending withinthe lateral side members 15. The pulley system may have the additionalbenefit of providing a timing system which ensures that movements ofopposite sides of the roll-in cot 10 are synchronized (e.g., each of thefront legs 20, each of the back legs 40, and/or other components). Thetiming system may be achieved by arranging carriage tension members 120and pulleys 122 in the embodiment depicted in FIG. 11, wherein thecarriage tension member 120 is crossed to ensure that one front leg 20cannot move separately from the other front leg 20. As used herein, thephrase “tension member” means a substantially flexible elongatestructure capable of conveying force through tension such as, forexample, a cable, a cord, a belt, a linkage, a chain, and the like.

Referring now to FIG. 9, in some embodiments the roll-in cot 10 cancomprise a timing belt and gear system 201. The gear system 201comprises a timing belt 130 that is disposed within at least a portionof a front leg 20. The timing belt 130 is engaged with gears 132 thatare pivotingly coupled to the front leg 20. One of the gears 132 iscoupled to the front hinge member 24 and one of the gears is coupled tothe front wheel linkage 27 such that the front linkage can rotate aroundan axis of rotation 134. The front hinge member 24, which pivots aroundan axis of rotation 136 as the front leg 20 is actuated, causes the gear132 to pivot with respect to the front leg 20. As the gear 132 coupledto the front hinge member 24 rotates, the timing belt 130 communicatesthe rotation to the gear 132 coupled to the front wheel linkage 27. Inthe embodiment depicted in FIG. 9, the gear 132 coupled to the fronthinge member 24 is half the diameter of the gear 132 coupled to thefront wheel linkage. Thus, a rotation 41 of the front hinge member 24will cause a rotation 42 of the front wheel linkage 27 of half themagnitude of the rotation 41 of the front hinge member 24. Specifically,when the front hinge member 24 rotates 10°, the front wheel linkage 27will only rotate 5°, due to the diameter disparity. In addition to atiming belt and gear system 201 as described herein, it is contemplatedthat other components, e.g., a hydraulic system or rotation sensors,could also be utilized herein. That is, the timing belt and gear system201 may be replaced with an angle detection sensor and a servomechanismthat actuates the front wheel linkage 27. As used herein, the phrase“timing belt” means any tension member configured to frictionally engagea gear or a pulley.

In further embodiments, both of the front legs 20 can comprise a timingbelt and gear system 201. In such embodiments, raising or lowering thefront end 17 of the support frame 12 by the front legs 20 trigger therotation of the front wheel linkage 27. Additionally, the back legs 40may comprise a timing belt and gear system 201, wherein the raising orlowering of the back end 19 of the support frame 12 by the back legs 40triggers the rotation of the back wheel linkage 47. Specifically,rotation of the back hinge member 44 with respect to the back leg 40around the axis of rotation 136 can cause the back wheel linkage 47 withrespect to the back leg 40 around the axis of rotation 134. Thus inembodiments where each of the front legs 20 and the back legs 40comprise a timing belt and gear system 201, the front wheels 26 and backwheels 46 can be rotated to ensure that the front wheels 26 and backwheels 46 can roll across surfaces at various cot heights. Thus, theroll-in cot 10 may be rolled side to side at any height when the supportframe 12 is substantially parallel to the ground, i.e., the front legs20 and the back legs 40 are actuated to substantially the same length.

Referring again to FIG. 3, the roll-in cot 10 may comprise a frontactuator sensor 62 and a back actuator sensor 64 configured to detectwhether a force is applied to or exerted by the front and back actuators16, 18, respectively. In some embodiments, the front actuator sensor 62and the back actuator sensor 64 can be configured to detect whether thefront and back actuators 16, 18 are under tension or compression. Asused herein, the term “tension” means that a pulling force is beingdetected by the sensor. Such a pulling force is commonly associated withthe load being removed from the legs coupled to the actuator, i.e., theleg and or wheels are being suspended from the support frame 12 withoutmaking contact with a surface beneath the support frame 12. Furthermore,as used herein the term “compression” means that a pushing force isbeing detected by the sensor. Such a pushing force is commonlyassociated with a load being applied to the legs coupled to theactuator, i.e., the leg and or wheels are in contact with a surfacebeneath the support frame 12 and transfer a compressive strain on thecoupled actuator. In one embodiment, the front actuator sensor 62 andthe back actuator sensor 64 are coupled to the support frame 12;however, other locations or configurations are contemplated herein. Thesensors may be proximity sensors, strain gauges, load cells, hall-effectsensors, or any other suitable sensor operable to detect when the frontactuator 16 and/or back actuator 18 are under tension or compression. Infurther embodiments, the front actuator sensor 62 and the back actuatorsensor 64 may be operable to detect the weight of a patient disposed onthe roll-in cot 10 (e.g., when strain gauges are utilized).

Referring to FIGS. 1-4, the movement of the roll-in cot 10 may becontrolled via the operator controls. Referring again to the embodimentof FIG. 1, the back end 19 may comprise operator controls for theroll-in cot 10. As used herein, the operator controls are the componentsused by the operator in the loading and unloading of the roll-in cot 10by controlling the movement of the front legs 20, the back legs 40, andthe support frame 12. Referring to FIG. 2, the operator controls maycomprise one or more hand controls 57 (for example, buttons ontelescoping handles) disposed on the back end 19 of the roll-in cot 10.Moreover, the operator controls may include a control box 50 disposed onthe back end 19 of the roll-in cot 10, which is used by the cot toswitch from the default independent mode and the synchronized or “sync”mode. The control box 50 may comprise one or more buttons 54, 56 whichplace in the cot in sync mode, such that both the front legs 20 and backlegs 40 can be raised and lowered simultaneously. In a specificembodiment, the sync mode may only be temporary and cot operation willreturn to the default mode after a period of time, for example, about 30seconds. In a further embodiment, the sync mode may be utilized inloading and/or unloading the roll-in cot 10. While various positions arecontemplated, the control box may be disposed between the handles on theback end 19.

As an alternative to the hand control embodiment, the control box 50 mayalso include a component which may be used to raise and lower theroll-in cot 10. In one embodiment, the component is a toggle switch 52,which is able to raise (+) or lower (−) the cot. Other buttons,switches, or knobs are also suitable. Due to the integration of thesensors in the roll-in cot 10, as is explained in greater detail herein,the toggle switch 52 may be used to control the front legs 20 or backlegs 40 which are operable to be raised, lowered, retracted or releaseddepending on the position of the roll-in cot 10. In one embodiment thetoggle switch is analog (i.e., the pressure and/or displacement of theanalog switch is proportional to the speed of actuation). The operatorcontrols may comprise a visual display component 58 configured to informan operator whether the front and back actuators 16, 18 are activated ordeactivated, and thereby may be raised, lowered, retracted or released.While the operator controls are disposed at the back end 19 of theroll-in cot 10 in the present embodiments, it is further contemplatedthat the operator controls be positioned at alternative positions on thesupport frame 12, for example, on the front end 17 or the sides of thesupport frame 12. In still further embodiments, the operator controlsmay be located in a removably attachable wireless remote control thatmay control the roll-in cot 10 without physical attachment to theroll-in cot 10.

In other embodiments as shown in FIG. 4, the roll-in cot 10 may furthercomprise a light strip 140 configured to illuminate the roll-in cot 10in poor lighting or poor visibility environments. The light strip 140may comprise LED's, light bulbs, phosphorescent materials, orcombinations thereof. The light strip 140 may be triggered by a sensorwhich detects poor lighting or poor visibility environments.Additionally, the cot may also comprise an on/off button or switch forthe light strip 140. While the light strip 140 is positioned along theside of the support frame 12 in the embodiment of FIG. 4, it iscontemplated that the light strip 140 could be disposed on the frontand/or back legs 20, 40, and various other locations on the roll-in cot10. Furthermore it is noted that the light strip 140 may be utilized asan emergency beacon analogous to ambulance emergency lights. Such anemergency beacon is configured to sequence the warning lights in amanner that draws attention to the emergency beacon and that mitigateshazards such as, for example photosensitive epilepsy, glare andphototaxis.

Turning now to embodiments of the roll-in cot 10 being simultaneouslyactuated, the cot of FIG. 4 is depicted as extended, thus front actuatorsensor 62 and back actuator sensor 64 detect that the front actuator 16and the back actuator 18 are under compression, i.e., the front legs 20and the back legs 40 are in contact with a lower surface and are loaded.The front and back actuators 16 and 18 are both active when the frontand back actuator sensors 62, 64 detect both the front and backactuators 16, 18, respectively, are under compression and can be raisedor lowered by the operator using the operator controls as shown in FIG.2 (e.g., “−” to lower and “+” to raise).

Referring collectively to FIGS. 5A-5C, an embodiment of the roll-in cot10 being raised (FIGS. 5A-5C) or lowered (FIGS. 5C-5A) via simultaneousactuation is schematically depicted (note that for clarity the frontactuator 16 and the back actuator 18 are not depicted in FIGS. 5A-5C).In the depicted embodiment, the roll-in cot 10 comprises a support frame12 slidingly engaged with a pair of front legs 20 and a pair of backlegs 40. Each of the front legs 20 are rotatably coupled to a fronthinge member 24 that is rotatably coupled to the support frame 12 (e.g.,via carriage members 28, 48 (FIG. 8)). Each of the back legs 40 arerotatably coupled to a back hinge member 44 that is rotatably coupled tothe support frame 12. In the depicted embodiment, the front hingemembers 24 are rotatably coupled towards the front end 17 of the supportframe 12 and the back hinge members 44 that are rotatably coupled to thesupport frame 12 towards the back end 19.

FIG. 5A depicts the roll-in cot 10 in a lowest transport position (e.g.,the back wheels 46 and the front wheels 26 are in contact with asurface, the front leg 20 is slidingly engaged with the support frame 12such that the front leg 20 contacts a portion of the support frame 12towards the back end 19 and the back leg 40 is slidingly engaged withthe support frame 12 such that the back leg 40 contacts a portion of thesupport frame 12 towards the front end 17). FIG. 5B depicts the roll-incot 10 in an intermediate transport position, i.e., the front legs 20and the back legs 40 are in intermediate transport positions along thesupport frame 12. FIG. 5C depicts the roll-in cot 10 in a highesttransport position, i.e., the front legs 20 and the back legs 40positioned along the support frame 12 such that the front load wheels 70are at a maximum desired height which can be set to height sufficient toload the cot, as is described in greater detail herein.

The embodiments described herein may be utilized to lift a patient froma position below a vehicle in preparation for loading a patient into thevehicle (e.g., from the ground to above a loading surface of anambulance). Specifically, the roll-in cot 10 may be raised from thelowest transport position (FIG. 5A) to an intermediate transportposition (FIG. 5B) or the highest transport position (FIG. 5C) bysimultaneously actuating the front legs 20 and back legs 40 and causingthem to slide along the support frame 12. When being raised, theactuation causes the front legs to slide towards the front end 17 and torotate about the front hinge members 24, and the back legs 40 to slidetowards the back end 19 and to rotate about the back hinge members 44.Specifically, a user may interact with a control box 50 (FIG. 2) andprovide input indicative of a desire to raise the roll-in cot 10 (e.g.,by pressing “+” on toggle switch 52). The roll-in cot 10 is raised fromits current position (e.g., lowest transport position or an intermediatetransport position) until it reaches the highest transport position.Upon reaching the highest transport position, the actuation may ceaseautomatically, i.e., to raise the roll-in cot 10 higher additional inputis required. Input may be provided to the roll-in cot 10 and/or controlbox 50 in any manner such as electronically, audibly or manually.

The roll-in cot 10 may be lowered from an intermediate transportposition (FIG. 5B) or the highest transport position (FIG. 5C) to thelowest transport position (FIG. 5A) by simultaneously actuating thefront legs 20 and back legs 40 and causing them to slide along thesupport frame 12. Specifically, when being lowered, the actuation causesthe front legs to slide towards the back end 19 and to rotate about thefront hinge members 24, and the back legs 40 to slide towards the frontend 17 and to rotate about the back hinge members 44. For example, auser may provide input indicative of a desire to lower the roll-in cot10 (e.g., by pressing a “−” on toggle switch 52). Upon receiving theinput, the roll-in cot 10 lowers from its current position (e.g.,highest transport position or an intermediate transport position) untilit reaches the lowest transport position. Once the roll-in cot 10reaches its lowest height (e.g., the lowest transport position) theactuation may cease automatically. In some embodiments, the control box50 (FIG. 1) provides a visual indication that the front legs 20 and backlegs 40 are active during movement.

In one embodiment, when the roll-in cot 10 is in the highest transportposition (FIG. 5C), the front legs 20 are in contact with the supportframe 12 at a front-loading index 221 and the back legs 40 are incontact with the support frame 12 a back-loading index 241. While thefront-loading index 221 and the back-loading index 241 are depicted inFIG. 5C as being located near the middle of the support frame 12,additional embodiments are contemplated with the front-loading index 221and the back-loading index 241 located at any position along the supportframe 12. For example, the highest transport position may be set byactuating the roll-in cot 10 to the desired height and providing inputindicative of a desire to set the highest transport position (e.g.,pressing and holding the “+” and “−” on toggle switch 52 simultaneouslyfor 10 seconds).

In another embodiment, any time the roll-in cot 10 is raised over thehighest transport position for a set period of time (e.g., 30 seconds),the control box 50 provides an indication that the roll-in cot 10 hasexceeded the highest transport position and the roll-in cot 10 needs tobe lowered. The indication may be visual, audible, electronic orcombinations thereof.

When the roll-in cot 10 is in the lowest transport position (FIG. 5A),the front legs 20 may be in contact with the support frame 12 at afront-flat index 220 located near the back end 19 of the support frame12 and the back legs 40 may be in contact with the support frame 12 aback-flat index 240 located near the front end 17 of the support frame12. Furthermore, it is noted that the term “index,” as used herein meansa position along the support frame 12 that corresponds to a mechanicalstop or an electrical stop such as, for example, an obstruction in achannel formed in a lateral side member 15, a locking mechanism, or astop controlled by a servomechanism.

The front actuator 16 is operable to raise or lower a front end 17 ofthe support frame 12 independently of the back actuator 18. The backactuator 18 is operable to raise or lower a back end 19 of the supportframe 12 independently of the front actuator 16. By raising the frontend 17 or back end 19 independently, the roll-in cot 10 is able tomaintain the support frame 12 level or substantially level when theroll-in cot 10 is moved over uneven surfaces, for example, a staircaseor hill. Specifically, if one of the front legs 20 or the back legs 40is in tension, the set of legs not in contact with a surface (i.e., theset of legs that is in tension) is activated by the roll-in cot 10(e.g., moving the roll-in cot 10 off of a curb). Further embodiments ofthe roll-in cot 10 are operable to be automatically leveled. Forexample, if back end 19 is lower than the front end 17, pressing the “+”on toggle switch 52 raises the back end 19 to level prior to raising theroll-in cot 10, and pressing the “−” on toggle switch 52 lowers thefront end 17 to level prior to lowering the roll-in cot 10.

In one embodiment, depicted in FIG. 2, the roll-in cot 10 receives afirst load signal from the front actuator sensor 62 indicative of afirst force acting upon the front actuator 16 and a second load signalfrom the back actuator sensor 64 indicative of a second force actingupon a back actuator 18. The first load signal and second load signalmay be processed by logic executed by the control box 50 to determinethe response of the roll-in cot 10 to input received by the roll-in cot10. Specifically, user input may be entered into the control box 50. Theuser input is received as control signal indicative of a command tochange a height of the roll-in cot 10 by the control box 50. Generally,when the first load signal is indicative of tension and the second loadsignal is indicative of compression, the front actuator actuates thefront legs 20 and the back actuator 18 remains substantially static(e.g., is not actuated). Therefore, when only the first load signalindicates a tensile state, the front legs 20 may be raised by pressingthe “−” on toggle switch 52 and/or lowered by pressing the “+” on toggleswitch 52. Generally, when the second load signal is indicative oftension and the first load signal is indicative of compression, the backactuator 18 actuates the back legs 40 and the front actuator 16 remainssubstantially static (e.g., is not actuated). Therefore, when only thesecond load signal indicates a tensile state, the back legs 40 may beraised by pressing the “−” on toggle switch 52 and/or lowered bypressing the “+” on toggle switch 52. In some embodiments, the actuatorsmay actuate relatively slowly upon initial movement (i.e., slow start)to mitigate rapid jostling of the support frame 12 prior to actuatingrelatively quickly.

Referring collectively to FIGS. 5C-6E, independent actuation may beutilized by the embodiments described herein for loading a patient intoa vehicle (note that for clarity the front actuator 16 and the backactuator 18 are not depicted in FIGS. 5C-6E). Specifically, the roll-incot 10 can be loaded onto a loading surface 500 according the processdescribed below. First, the roll-in cot 10 may be placed into thehighest transport position (FIG. 5C) or any position where the frontload wheels 70 are located at a height greater than the loading surface500. When the roll-in cot 10 is loaded onto a loading surface 500, theroll-in cot 10 may be raised via front and back actuators 16 and 18 toensure the front load wheels 70 are disposed over a loading surface 500.In one embodiment, depicted in FIG. 10, as the roll-in cot 10 continuesbeing loaded, the hook engagement bar 80 may be swiveled over theloading surface hook 550 of a loading surface 500 (e.g., an ambulanceplatform). Then, the roll-in cot 10 may be lowered until front loadwheels 70 contact the loading surface 500 (FIG. 6A).

As is depicted in FIG. 6A, the front load wheels 70 are over the loadingsurface 500. In one embodiment, after the load wheels contact theloading surface 500 the front pair of legs 20 can be actuated with thefront actuator 16 because the front end 17 is above the loading surface500. As depicted in FIGS. 6A and 6B, the middle portion of the roll-incot 10 is away from the loading surface 500 (i.e., a large enoughportion of the roll-in cot 10 has not been loaded beyond the loadingedge 502 such that most of the weight of the roll-in cot 10 can becantilevered and supported by the wheels 70, 26, and/or 30). When thefront load wheels are sufficiently loaded, the roll-in cot 10 may beheld level with a reduced amount of force.

Additionally, in such a position, the front actuator 16 is in tensionand the back actuator 18 is in compression. Thus, for example, if the“−” on toggle switch 52 is activated, the front legs 20 are raised (FIG.6B). In one embodiment, after the front legs 20 have been raised enoughto trigger a loading state, the operation of the front actuator 16 andthe back actuator 18 is dependent upon the location of the roll-in cot.In some embodiments, upon the front legs 20 raising, a visual indicationis provided on the visual display component 58 of the control box 50(FIG. 2). The visual indication may be color-coded (e.g., activated legsin green and non-activated legs in red). This front actuator 16 mayautomatically cease to operate when the front legs 20 have been fullyretracted. Furthermore, it is noted that during the retraction of thefront legs 20, the front actuator sensor 62 may detect tension, at whichpoint, front actuator 16 may raise the front legs 20 at a higher rate,for example, fully retract within about 2 seconds.

After the front legs 20 have been retracted, the roll-in cot 10 may beurged forward until the intermediate load wheels 30 have been loadedonto the loading surface 500 (FIG. 6C). As depicted in FIG. 6C, thefront end 17 and the middle portion of the roll-in cot 10 are above theloading surface 500. As a result, the pair of back legs 40 can beretracted with the back actuator 18. Specifically, an ultrasonic sensormay be positioned to detect when the middle portion is above the loadingsurface 500. When the middle portion is above the loading surface 500during a loading state (e.g., the front legs 20 and back legs 40 have anangle delta greater than the loading state angle), the back actuator maybe actuated. In one embodiment, an indication may be provided by thecontrol box 50 (FIG. 2) when the intermediate load wheels 30 aresufficiently beyond the loading edge 502 to allow for back leg 40actuation (e.g., an audible beep may be provided).

It is noted that, the middle portion of the roll-in cot 10 is above theloading surface 500 when any portion of the roll-in cot 10 that may actas a fulcrum is sufficiently beyond the loading edge 502 such that theback legs 40 may be retracted a reduced amount of force is required tolift the back end 19 (e.g., less than half of the weight of the roll-incot 10, which may be loaded, needs to be supported at the back end 19).Furthermore, it is noted that the detection of the location of theroll-in cot 10 may be accomplished by sensors located on the roll-in cot10 and/or sensors on or adjacent to the loading surface 500. Forexample, an ambulance may have sensors that detect the positioning ofthe roll-in cot 10 with respect to the loading surface 500 and/orloading edge 502 and communications means to transmit the information tothe roll-in cot 10.

Referring to FIG. 6D, after the back legs 40 are retracted and theroll-in cot 10 may be urged forward. In one embodiment, during the backleg retraction, the back actuator sensor 64 may detect that the backlegs 40 are unloaded, at which point, the back actuator 18 may raise theback legs 40 at higher speed. Upon the back legs 40 being fullyretracted, the back actuator 18 may automatically cease to operate. Inone embodiment, an indication may be provided by the control box 50(FIG. 2) when the roll-in cot 10 is sufficiently beyond the loading edge502 (e.g., fully loaded or loaded such that the back actuator is beyondthe loading edge 502).

Once the cot is loaded onto the loading surface (FIG. 6E), the front andback actuators 16, 18 may be deactivated by being lockingly coupled toan ambulance. The ambulance and the roll-in cot 10 may each be fittedwith components suitable for coupling, for example, male-femaleconnectors. Additionally, the roll-in cot 10 may comprise a sensor whichregisters when the roll-in cot 10 is fully disposed in the ambulance,and sends a signal which results in the locking of the actuators 16, 18.In yet another embodiment, the roll-in cot 10 may be connected to a cotfastener, which locks the actuators 16, 18, and is further coupled tothe ambulance's power system, which charges the roll-in cot 10. Acommercial example of such ambulance charging systems is the IntegratedCharging System (ICS) produced by Ferno-Washington, Inc.

Referring collectively to FIGS. 6A-6E, independent actuation, as isdescribed above, may be utilized by the embodiments described herein forunloading the roll-in cot 10 from a loading surface 500. Specifically,the roll-in cot 10 may be unlocked from the fastener and urged towardsthe loading edge 502 (FIG. 6E to FIG. 6D). As the back wheels 46 arereleased from the loading surface 500 (FIG. 6D), the back actuatorsensor 64 detects that the back legs 40 are unloaded and allows the backlegs 40 to be lowered. In some embodiments, the back legs 40 may beprevented from lowering, for example if sensors detect that the cot isnot in the correct location (e.g., the back wheels 46 are above theloading surface 500 or the intermediate load wheels 30 are away from theloading edge 502). In one embodiment, an indication may be provided bythe control box 50 (FIG. 2) when the back actuator 18 is activated(e.g., the intermediate load wheels 30 are near the loading edge 502and/or the back actuator sensor 64 detects tension).

When the roll-in cot 10 is properly positioned with respect to theloading edge 502, the back legs 40 can be extended (FIG. 6C). Forexample, the back legs 40 may be extended by pressing the “+” on toggleswitch 52. In one embodiment, upon the back legs 40 lowering, a visualindication is provided on the visual display component 58 of the controlbox 50 (FIG. 2). For example, a visual indication may be provided whenthe roll-in cot 10 is in a loading state and the back legs 40 and/orfront legs 20 are actuated. Such a visual indication may signal that theroll-in cot should not be moved (e.g., pulled, pushed, or rolled) duringthe actuation. When the back legs 40 contact the floor (FIG. 6C), theback legs 40 become loaded and the back actuator sensor 64 deactivatesthe back actuator 18.

When a sensor detects that the front legs 20 are clear of the loadingsurface 500 (FIG. 6B), the front actuator 16 is activated. In oneembodiment, when the intermediate load wheels 30 are at the loading edge502 an indication may be provided by the control box 50 (FIG. 2). Thefront legs 20 are extended until the front legs 20 contact the floor(FIG. 6A). For example, the front legs 20 may be extended by pressingthe “+” on toggle switch 52. In one embodiment, upon the front legs 20lowering, a visual indication is provided on the visual displaycomponent 58 of the control box 50 (FIG. 2).

Referring back to FIGS. 4 and 10, in embodiments where the hookengagement bar 80 is operable to engage with a loading surface hook 550on a loading surface 500, the hook engagement bar 80 is disengaged priorto unloading the roll-in cot 10. For example, hook engagement bar 80 maybe rotated to avoid the loading surface hook 550. Alternatively, theroll-in cot 10 may be raised from the position depicted in FIG. 4 suchthat the hook engagement bar 80 avoids the loading surface hook 550.

Referring collectively to FIGS. 6A to 6E, embodiments of the roll-in cot10 can be configured to facilitate loading and unloading. Specifically,the front legs 20 and the back legs 40 can include geometric featuresthat can reduce the amount of force needed to hold the roll-in cot 10level. Accordingly, the middle portion of the roll-in cot 10 can operateas a fulcrum that facilitates loading and unloading, i.e., the geometricfeatures of the front legs 20 and the back legs 40 can enhance thebalance of the roll-in cot 10 during loading and unloading. For example,the arrangement of the intermediate load wheel 30 along the front leg 20can enhance the balance of a roll-in cot 10 when supporting a patientduring loading and unloading.

Referring now to FIG. 6A, the front leg 20 can define a front leg span32 that extends along the front leg 20 from the front carriage member 28through the front wheel linkage 27. A distance 33 of the front leg span32 can be measured between the carriage member 28 and the axis ofrotation 134. The front wheel 26 can be offset from the support frame 12by the distance 33 of the front leg span 32. A hinge member distance 34can be defined along the front leg span 32 between the axis of rotation136 and the axis of rotation 134. Thus, the intersection between thefront hinge member 24 and the front leg 20 can be offset from the frontwheels by the hinge member distance. Additionally, a load wheel distance36 can be defined along the front leg span 32 between the axis ofrotation 136 and the intermediate load wheel 30. Accordingly, theintermediate load wheel 30 can be offset from the front wheel 26 by theload wheel distance 36. The applicants have discovered that therelationships between the distance 33 of the front leg span 32 and eachof the hinge member distance 34 and the load wheel distance 36 can beconfigured to enhance the balance of the roll-in cot 10 during loadingand unloading. In some embodiments, the load wheel distance 36 can beless than about 50% of the distance 33 of the front leg span 32 such as,for example, less than about 45% in one embodiment. In furtherembodiments, the load wheel distance 36 can be between about 50% and 20%of the distance 33 of the front leg span 32 such as, for example,between about 45% and 35% of the distance 33 of the front leg span 32 inone embodiment, or between about 40% and 30% of the distance 33 of thefront leg span 32 in another embodiment. Alternatively or additionally,the hinge member distance 34 can be greater than about 50% of thedistance 33 of the front leg span 32 such as, for example, greater thanabout 60% in one embodiment, or greater than about 70% in anotherembodiment. In further embodiments, the hinge member distance 34 can bebetween about 55% and 90% of the distance 33 of the front leg span 32such as, for example, between about 65% and 85% of the distance 33 ofthe front leg span 32 in one embodiment, or between about 70% and 80% ofthe distance 33 of the front leg span 32 in another embodiment.Accordingly, the hinge member distance 34 can be greater than the loadwheel distance 36.

Referring now to FIG. 6C, the arrangement of back leg 40 with respect tothe front leg 20 can enhance the balance of the roll-in cot 10 duringloading and unloading. For example, the arrangement of back leg 40during loading and unloading from the loading surface 500 can improvethe fulcrum effect of the middle portion of the roll-in cot 10. In someembodiments, the back leg 40 can be configured to form a loading angle αwith respect to a loading level 504 during loading and unloading.Specifically, the back leg 40 can define a back leg span 38 that extendsalong the back leg 40 from the back carriage member 48 through the backwheel linkage 47 and that forms the loading angle α with respect to aloading level 504 during loading and unloading. A distance 39 of theback leg span 38 can be measured between the back carriage member 48 andthe axis of rotation 134 of the back wheel linkage 47. Accordingly, theback wheel 46 can be offset from the support frame 12 by the distance 39of the back leg span 38. In some embodiments, the distance 39 of theback leg span 38 can be substantially equal to the distance 33 of thefront leg span 32 (FIG. 6A).

As is described in greater detail above, during loading or unloading,the intermediate load wheel 30, the front wheel 26 and the front loadwheel 70 can be in contact with the loading surface 500. Accordingly,the outer diameters of the intermediate load wheel 30, the front wheel26 and the front load wheel 70 can be substantially aligned. The loadinglevel 504 can be defined by the alignment of the outer diameters of theintermediate load wheel 30, the front wheel 26, the front load wheel 70,the loading surface 500, or any combination thereof. The back leg span38 of the back leg 40 can be configured to form a loading angle α withrespect to the loading level 504. In embodiments where the loading level504 is substantially parallel to the support frame 12 of the roll-in cot10, the back leg span 38 of the back leg 40 can be configured to formthe loading angle α with respect to the support frame 12 of the roll-incot 10. In some embodiments, the loading angle α can be substantiallyacute such as, for example, less than about 85° (about 1.48 radians) inone embodiment, between about 75° (about 1.31 radians) and about 40°(about 0.70 radians) in another embodiment, or between about 60° (about1.05 radians) and about 45° (about 0.79 radians) in a furtherembodiment.

As is noted above, the arrangement of back leg 40 with respect to thefront leg 20 can enhance the balance of the roll-in cot 10 duringloading and unloading. For example, when the intermediate load wheel 30,the front wheel 26 and the front load wheel 70 are aligned along theloading level 504, the intermediate load wheel 30 can be offset from theback leg 40 by a loading span 506. The loading span 506 can be measuredalong the loading level 504 between an axis of rotation 31 of theintermediate load wheel 30 (e.g., a wheel axle) and the back leg 40.

Referring collectively to FIGS. 6A and 6C, the loading span 506 can beless than the load wheel distance 36 such as, for example, the loadingspan 506 can be less than about 95% of the load wheel distance 36 in oneembodiment, or the loading span 506 can be between about 50% and about95% of the load wheel distance 36 in another embodiment. In furtherembodiments, the loading span 506 can be between about 4 inches (about15.2 cm) and about 24 inches (about 61 cm) such as, for example, betweenabout 5 inches (about 25.4 cm) and about 12 inches (about 45.7 cm) inanother embodiment.

Referring again to FIG. 6C, the back leg span 38 of the back leg 40 canbe configured to form a back leg angle θ with respect to an intermediatespan 142 during loading and unloading. The intermediate span 142 can bedemarcated by the axis of rotation 31 of the intermediate load wheel 30(e.g., a wheel axle) and the back carriage member 48. In someembodiments, the back leg angle θ can be configured to enhance thebalance of the roll-in cot 10 during loading and unloading.Specifically, when loading or unloading the roll-in cot 10, the back leg40 can be supported by a surface that is lower than the loading surface500 and the intermediate load wheel 30 can be supported by the loadingsurface 500. For example, the back wheel 46 can be supported by theground or a floor, while the intermediate load wheel 30 is supported bya floor of an ambulance. According to the embodiments described herein,the back leg angle θ can be substantially acute, when the back leg 40 issupported by a surface that is lower than the loading surface 500 andthe intermediate load wheel 30 is supported by the loading surface 500such as, for example, less than about 85° (about 1.48 radians) in oneembodiment, between about 60° (about 1.05 radians) and about 80° (about1.40 radians) in another embodiment.

According to the embodiments described herein, the roll-in cot 10 can beconfigured to be load balanced towards the front end 17 of the roll-incot 10. As used herein, the phrase “configured to be load balanced”refers to a center of gravity of a cot-patient combination. As usedherein the phrase “cot-patient combination” can mean the resultantcombination of the roll-in cot 10 and an anthropomorphic test device 508such that the top of the head of the anthropomorphic test device 508 isin line with the center of the front load wheel 70. Additionally, it isnoted that the phrase “anthropomorphic test device” refers to a 95^(th)Percentile Adult Male Hybrid III Dummy as defined by the NationalHighway Traffic Safety Administration. The anthropomorphic test device508 can be supported directly by the support frame 12 or indirectly viapatient supporting structure, which is in turn supported by the supportframe 12. In some embodiments, the roll-in cot 10 can be configured tobe load balanced forward (i.e., towards the front end 17 of the roll-incot 10) with respect to the intermediate load wheel 30, when the frontleg 20 of the roll-in cot 10 is retracted towards the support frame 12.Examples of the front leg 20 being retracted towards the support frameare depicted in FIGS. 5A, and 6B-6E. Thus, in some embodiments, when theback leg 40 is supported by a surface that is lower than the loadingsurface 500 and the intermediate load wheel 30 is supported by theloading surface 500, the cot-patient combination can have a center ofgravity that is forward of the intermediate load wheel 30.

Referring now to FIG. 12, the back leg 40 can comprise a sinuousinternal edge 144 configured to assist with unloading the roll-in cot10. The sinuous internal edge 144 can be formed along the portion of theback leg 40 that is facing the front end 17 of the roll-in cot 10. Insome embodiments, the sinuous internal edge 144 can be formed from oneor more facets, one or more polynomial shaped contours, or combinationsthereof. For example, the sinuous internal edge 144 can comprise a firstedge segment 146, a second edge segment 147, and a third edge segment148. As used herein, the phrase “edge segment” can mean a partition ofan edge. Thus an edge segment can be a partition of a substantiallycurved line, a substantially straight line, or combinations thereof. Thefirst edge segment 146 can be located towards the top of the sinuousinternal edge 144, i.e., towards the intersection of the back leg 40 andthe support frame 12. The third edge segment 148 can be located towardsthe bottom of the sinuous internal edge 144, i.e., towards the backwheel 46. The second edge segment 147 can be located between the firstedge segment 146 and the third edge segment 148.

In some embodiments, the sinuous internal edge 144 of the back leg 40can comprise an upper angle β formed between the first edge segment 146and the second edge segment 147. The upper angle β can be configuredsuch that extension of the back leg 40 imparts an unloading force 510upon the roll-in cot 10. Specifically, as the back leg 40 extends, thesinuous internal edge 144 of the back leg 40 can contact (depicted inFIG. 12 as a dashed line object) the loading surface 500, the loadingedge 502, or both. When such contact is made, extension of the back leg40 can generate the unloading force 510 and urge the roll-in cot 10along the direction of the unloading force 510. In some embodiments, theupper angle β can be formed to enhance contact between the second edgesegment 147 of the sinuous internal edge 144 and the loading surface500, the loading edge 502, or both. Specifically, the upper angle θ canbe substantially obtuse such as, for example, between about 140° (about2.44 radians) and about 175° (about 3.05 radians) in one embodiment, orbetween about 155° (about 2.71 radians) and about 175° (about 3.05radians) in another embodiment, or between about 160° (about 2.79radians) and about 170° (about 2.97 radians) in a further embodiment.

Alternatively or additionally, the sinuous internal edge 144 of the backleg 40 can comprise a lower angle φ formed between the second edgesegment 147 and the third edge segment 148. The lower angle φ can beconfigured to provide clearance between the back leg 40 and the loadingedge 502, when the back leg 40 is fully extended. The lower angle φ canbe a reflex angle such as, for example, between about 185° (about 3.23radians) and about 240° (about 4.19 radians) in one embodiment, orbetween about 195° (about 3.40 radians) and about 230° (about 4.01radians) in another embodiment, or between about 205° (about 3.58radians) and about 220° (about 3.84 radians) in a further embodiment.

In embodiments where the sinuous internal edge 144 comprises both theupper angle β and the lower angle φ, the upper angle β and the lowerangle φ can be defined in combination such that the intersection betweenthe back hinge member 44 and the back leg 40 is disposed substantiallyin line with the back leg span 38. In some embodiments, the upper angleβ can be located above the axis of rotation 136 of the back hinge member44. For example, the upper angle β can be closer to the support frame 12than the axis of rotation 136 of the back hinge member 44 as measuredalong the back leg span 38. Alternatively or additionally, and the lowerangle φ can be located below the axis of rotation 136 of the back hingemember 44. For example, the lower angle φ can be further from thesupport frame 12 than the axis of rotation 136 of the back hinge member44 as measured along the back leg span 38. Accordingly, the upper angleβ of the sinuous internal edge 144 can be located above the lower angleφ of the sinuous internal edge 144.

It should now be understood that the embodiments described herein may beutilized to transport patients of various sizes by coupling a supportsurface such as a patient support surface to the support frame. Forexample, a lift-off stretcher or an incubator may be removably coupledto the support frame. Therefore, the embodiments described herein may beutilized to load and transport patients ranging from infants tobariatric patients. Furthermore the embodiments described herein, may beloaded onto and/or unloaded from an ambulance by an operator holding asingle button to actuate the independently articulating legs (e.g.,pressing the “−” on the toggle switch to load the cot onto an ambulanceor pressing the “+” on the toggle switch to unload the cot from anambulance). Specifically, the roll-in cot 10 may receive an input signalsuch as from the operator controls. The input signal may be indicativeof a first direction or a second direction (i.e., lower or raise). Thepair of front legs and the pair of back legs may be loweredindependently when the signal is indicative of the first direction ormay be raised independently when the signal is indicative of the seconddirection.

It is further noted that terms like “preferably,” “generally,”“commonly,” and “typically” are not utilized herein to limit the scopeof the claimed embodiments or to imply that certain features arecritical, essential, or even important to the structure or function ofthe claimed embodiments. Rather, these terms are merely intended tohighlight alternative or additional features that may or may not beutilized in a particular embodiment of the present disclosure.

For the purposes of describing and defining the present disclosure it isadditionally noted that the term “substantially” is utilized herein torepresent the inherent degree of uncertainty that may be attributed toany quantitative comparison, value, measurement, or otherrepresentation. The term “substantially” is also utilized herein torepresent the degree by which a quantitative representation may varyfrom a stated reference without resulting in a change in the basicfunction of the subject matter at issue.

Having provided reference to specific embodiments, it will be apparentthat modifications and variations are possible without departing fromthe scope of the present disclosure defined in the appended claims. Morespecifically, although some aspects of the present disclosure areidentified herein as preferred or particularly advantageous, it iscontemplated that the present disclosure is not necessarily limited tothese preferred aspects of any specific embodiment.

What is claimed is:
 1. A cot comprising: a support frame for supportinga patient above a loading surface of an emergency vehicle; a pair ofback legs pivotally coupled to the support frame; a back actuator toextend and retract the pair of back legs relative to the support frame,wherein operation of the back actuator is dependent upon a location ofthe cot relative to the loading surface; and a plurality of sensors atleast one of which detects the loading surface and at least one of whichcooperates with the back actuator such that upon a signal received fromthe at least one sensor that detects the loading surface and furtherupon a signal received from the at least one sensor which cooperateswith the back actuator that the pair of back legs are unloaded duringretraction, the back actuator raises the pair of back legs at a higherspeed from an initial speed.
 2. The cot according to claim 1, whereinthe at least one sensor that detects the loading surface comprises atleast one sensor that is on or adjacent to the loading surface such thatdetection of the location of the cot is accomplished through receipt ofinformation from the at least one sensor that is on or adjacent to theloading surface to the cot via communications means of the emergencyvehicle.
 3. The cot according to claim 1, further comprising: a pair offront legs pivotally coupled to the support frame; a front actuator toextend and retract the pair of front legs relative to the support frameindependently from the pair of back legs; and at least one sensor whichupon detecting tension of the pair of front legs during retraction, thefront actuator raises the pair of front legs at a higher rate from aninitial speed.
 4. The cot according to claim 1, wherein the at least onesensor which detects the loading surface is associated with a front loadwheel that is coupled to the support frame such that the at least onesensor which detects the loading surface is operable to detect alocation of the front load wheel with respect to the loading surface. 5.The cot according to claim 4, wherein the at least one sensor whichdetects the loading surface comprises an ultrasonic sensor, a touchsensor, a proximity sensor, or other sensors effective to detect whenthe front load wheel is above the loading surface.
 6. The cot accordingto claim 1, wherein the at least one sensor which detects the loadingsurface is associated with an intermediate load wheel such that when theintermediate load wheel is within a set distance of the loading surfacethe at least one sensor which detects the loading surface provides asignal which causes activation of the back actuator.
 7. The cotaccording to claim 3, wherein once the cot is loaded onto the loadingsurface, the front and back actuators are deactivated by being lockinglycoupled to the emergency vehicle.
 8. The cot according to claim 1,wherein the plurality of sensors further comprises a sensor whichregisters when the cot is fully disposed in the emergency vehicle, andsends a signal which results in locking of the back actuator.
 9. The cotaccording to claim 1, wherein the cot connects to a cot fastener, whichlocks the actuators.
 10. The cot according to claim 1, furthercomprising a hook engagement bar, which is operable to engage with aloading surface hook on the loading surface to prevent the cot fromsliding backwards from the loading surface, wherein the hook engagementbar comprises a sensor which detects the engagement of the hookengagement bar and the loading surface hook, wherein the engagement ofthe hook engagement bar and the loading surface hook allows forretraction of the front legs for loading onto the loading surface. 11.The cot according to claim 10, wherein the sensor which detects theengagement of the hook engagement bar is a touch sensor, a proximitysensor, or any other sensor operable to detect the engagement of theloading surface hook.
 12. The cot according to claim 1, furthercomprising a locking mechanism to transition wheels of the pair of backlegs between a swiveling state and a directionally locked state.
 13. Thecot according to claim 1, further comprising a control box to which atleast one of the plurality of sensors sends the signal to causeactivation of the back actuator.
 14. The cot according to claim 13, inwhich the control box controls a visual display component that isconfigured to inform an operator whether the back actuator is activatedor deactivated.
 15. The cot according to claim 1, wherein the pluralityof sensors further comprises at least one sensor which registers whenthe cot is fully disposed in the emergency vehicle and is configured tosend a signal which results in locking of the back actuator upondetection of the cot being fully disposed in the emergency vehicle. 16.The cot according to claim 1, wherein the back actuator is deactivatedby being lockingly coupled to an ambulance.
 17. The cot according toclaim 16, wherein the cot couples to the ambulance via a male-femaleconnector.
 18. The cot according to claim 16, wherein the back actuatorlocks upon the cot being connected to a cot fastener.